The president of a limousine company questioned in a congressional bribery investigation has denied accusations that he or his company provided prostitutes to convicted former congressman Randy "Duke" Cunningham or anyone else. The company has turned over records to federal investigators and is cooperating with the probe, its lawyers said.

"We categorically deny any involvement in, or connection, with prostitution," Sandy Roberts, an attorney for Christopher D. Baker, president of Shirlington Limousine and Transportation Inc., said in a letter to The Washington Post. "Shirlington Limousine has never been a part of, nor involved in, any illicit or illegal activities that may have taken place in connection with Congressman Cunningham."

In recent weeks, federal investigators have been examining the relationship between Shirlington Limousine and Brent R. Wilkes, a San Diego businessman under investigation for bribing Cunningham to get federal contracts. Mitchell J. Wade, a defense contractor who has admitted to bribing the former congressman, told prosecutors that Wilkes used the limousine company to help procure paid escorts for Cunningham, a California Republican, and possibly other lawmakers and officials, according to a source close to the investigation. Wilkes has denied that allegation through his attorney.

Michael York, another Baker attorney, said yesterday that Baker was questioned several weeks ago by FBI agents about his dealings with Wilkes. At the government's request, Baker furnished the government with company records.

Shirlington Limousine had financial troubles for years before winning two transportation contracts from the Department of Homeland Security in 2004 and 2005 worth $25 million. Department officials said that Baker's company was not the low bidder on either contract, but that they were awarded for "best value," based on Shirlington Limousine's past performance and technical ability.

Homeland Security officials said they did not know that Shirlington Limousine lost a contract for shuttle bus service with Howard University in 2002 amid charges of poor service. Baker did not cite the university contract on his bid proposal, despite instructions to list recent contracts involving similar services.

If Homeland Security had known about the Howard contract or other previous financial problems of the company and its owner, officials said, Shirlington Limousine's bidding score might have been lower -- but not necessarily enough to give the contract to a competitor.

Officials said Baker's criminal record, which includes numerous misdemeanors and two felony convictions, would not have affected the company's bid. When the agency contracts with a company, officials said, they do not check the criminal backgrounds of its executives -- nor do they run their names against the government's terrorist watch list. In Shirlington Limousine's case, only the drivers' backgrounds were checked.

Clark Kent Ervin, the former inspector general for Homeland Security, said the vetting process was badly flawed because it left security gaps and failed to turn up readily available information about Shirlington Limousine's finances and performance.

Both contracts were awarded under a Small Business Administration program limiting competition to companies located in poor neighborhoods. The larger contract, worth as much as $21 million over five years, was awarded in fall 2005 to provide shuttle service between Homeland Security buildings and limo service for senior officials.

The award was challenged by a losing bidder who alleged that Shirlington Limousine falsely claimed to be located in a poor neighborhood, records show. To qualify, Shirlington Limousine listed as its principal office 425 Eighth St. NW, in downtown Washington, said Calvin Jenkins, an SBA contracting official. That address is a furnished residential apartment in a luxury building, a fact cited in the protest. The SBA denied the protest.

Jenkins said a residential apartment can qualify as a principal place of business if it is "the single location where the greatest number of individuals" report to work.

Cunningham has begun serving his sentence of eight years and four months. Wade, the defense contractor, pleaded guilty to his part in the scheme in February and is cooperating with investigators. Wilkes has not been charged.

Baker's connection to Wilkes began in the late 1990s when he was introduced to the contractor by Jerome Foster, a San Diego businessman who was then a director of Shirlington Limousine, Foster said in an interview.

Foster said he met Baker at the Watergate Hotel when he hired Baker as a driver. Baker told Foster that he had had legal and money troubles, Foster said, and he agreed to serve as a mentor to the driver.

At the time, Foster said, he had Navy contracts, used the same lobbying firm as Wilkes and was discussing doing business with Wilkes. He said he has not seen either man in years and was "shocked" when he learned about Baker's contracts.

Foster said the Baker he knew was naive about business. "He wasn't an individual I would have thought could have gotten that kind of contract on his own," Foster said.

Roberts, Baker's lawyer, said in the letter that Baker won the federal contracts because of his "commitment to detail and customer service."